you just saw outgoing secretary of defense leon panetta in his fair well speech at georgetown university. well, he also warned today that a hostile country could attack america by computer-- a 21st century pearl harbor. >> we are literally the targets of thousands of cyber attacks everyday. everyday. thousands of cyber attacks that are striking at the private sector, strike at silicon valley, strike at other institutions within our society, strike at government, strike at the department and our intelligence agencies. and cyber is now at a point where the technology is there to cripple a country, to take down our power grid system. to take down our government systems. take down our financial systems. and literally paralyze the country. >> pelley: now, the pentagon set up a cyber command to practice both offense and defense on the computer battlefield. now cyber command is expanding five-fold and we asked bob orr to look into who's behind the computer threat. >> reporter: despite its imposing facade, the u.s. federal reserve could not stop the latest attack. on sunday, hackers broke into a